I need help with idx pro silverdog red pcb!!

[Tibuck19]

This sounds like the 'resonant' of either the TX or RX coil/circuit is not what it used to be.
I know you said you replaced every poly cap but are the caps for TX or TX resonance good values?

Maybe try adding a cap across the RX cap while watching the signals on the scope.

The Caps that have been replace are the values on the silk screening, i bought a bunch of the them ( i have enough Caps to populate 3 boards if need be haha) and measured every single ones value between a few of them to get one that is the closest to what the silk screen is showing, is that what you meant? IDK Waltr, for everything to have shifted so much there has to be a resistance change somewhere along the board right? now checking each and every resistor out of circuit seems more time consuming that it is worth, Something somewhere changed big time, What i find odd is everyone tends to think that the 6b coils should not work with the idx, but i have used a 6b coil for almost two years without an issue and all of sudden they no longer work right, i just find it really odd that i was either able to get it to work out of dumb luck or idk what lol. i know the TGSL has a very noticeable phase shift, should the idx be the same? i will pull out the 680p cap and try to find something else with a lower and higher value to see if it changes anything,but again its what was in there while the 6b coil was working perfectly.

[waltr]

Also if i am not mistaken, doesn't the TX and RX need to be out of phase with each other? when i probe the tx coming out of pin 7 of U8(lm393) on channel one, and pin 7 of U1 (ne5534) on channel 2, the are both aligned with each other besides an amplitude difference.

This sounds like the 'resonant' of either the TX or RX coil/circuit is not what it used to be.
I know you said you replaced every poly cap but are the caps for TX or TX resonance good values?

Maybe try adding a cap across the RX cap while watching the signals on the scope.

[Tibuck19]

Good morning everyone, Here an update of what had been done and what is going on, as i mentioned, Replacing every poly cap and ic on the board and redoing all of the connections wiring... here are some of the results, With a homemade coil that don made and the F deepscan coil things are looking up as im now closer to 40 cm airtest on most coin from a penny to a quarter with gb pot at around 8k ish, However with both 6b coils the 8 inch( WHICH ALWAYS WORKED ON THIS IDX) and 15 inch it is a whole different story, no progress has been made, the ground balance pot is closer to 21K which means more amplitude on the TX side which seems to cause a step ladder effect on sine wave of RX when i probe pin 7 of the 5534 with a much much lower tx to rx aspect ratio, i will snap a few photos of the oscope later on to show you all what i mean, however with all four coils, there seems to be a shift in pot values, where before the pinpoint audible threshold was around 1/4 turn it is now at a little over halfway, the discrimination for a nickel which use to be at halfway is now 3/4 of the way on the Pot, Also if i am not mistaken, doesn't the TX and RX need to be out of phase with each other? when i probe the tx coming out of pin 7 of U8(lm393) on channel one, and pin 7 of U1 (ne5534) on channel 2, the are both aligned with each other besides an amplitude difference.

[Tibuck19]

No its not as i was getting close to 42 to 45 cm before this malfunction started
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sorry, but you have to add if mention the depth in WHAT mode you get this - ALL METALL MODE or DISC MODE.
sure misunderstanding what you write about.

for starters unless i'm mistaken which is very possible, the IDX red board does not have an all metal or disc mode, it has a normal beep detection mode and a Point point mode which is an audible threshold hummmm, the only way to get a metal mode as you might think of it, is to turn the Disc pot down to 0, in anycase, i was getting the 42- 45 in beep mode with disc pot halfway just before losing the nickels. hope that what you needed to know.

[kt315]

No its not as i was getting close to 42 to 45 cm before this malfunction started
---
sorry, but you have to add if mention the depth in WHAT mode you get this - ALL METALL MODE or DISC MODE.
sure misunderstanding what you write about.

[Koala]

The TGSL is better on low conductive (short TC) targets like nickles and the IDX is better on higher conductive (long TC) targets like silver coins. This is due to the operating frequencies use in these two detectors. Lower freq better for long TC and higher freq better for short TC.
Dbowers did a comparison of these two detectors on different target in his 'test garden'.

I have several coils for

IDX
Bandido
F1265X

the Fisher out preform the other two on all targets the rest of the machine makes more of a difference than the frequency

the Bandido and IDX can be made to run identical. But with real in the field settings the Bandido out preforms the IDX due to the better discrimination.

[waltr]

No its not as i was getting close to 42 to 45 cm before this malfunction started to happen loll my TGSL gets about 35CM and i missed a lot of stuff with it, after i detected over the same area with the IDX. heck there was at least two silver quarters the TGSL missed that i had found the year later with the IDX with the smaller 8 inch coil.( maybe it was experience that i had gain or maybe the idx is that much more better) hehehe i dont mean to sound so bios but the way the idx was working, i never felt the need to buy a commercial detector as they would of had a hard time being better.

The TGSL is better on low conductive (short TC) targets like nickles and the IDX is better on higher conductive (long TC) targets like silver coins. This is due to the operating frequencies use in these two detectors. Lower freq better for long TC and higher freq better for short TC.
Dbowers did a comparison of these two detectors on different target in his 'test garden'.

[Tibuck19]

:-))) yes, thats true ;-) . 35cm is very very good for this Project.

No its not as i was getting close to 42 to 45 cm before this malfunction started to happen loll my TGSL gets about 35CM and i missed a lot of stuff with it, after i detected over the same area with the IDX. heck there was at least two silver quarters the TGSL missed that i had found the year later with the IDX with the smaller 8 inch coil.( maybe it was experience that i had gain or maybe the idx is that much more better) hehehe i dont mean to sound so bios but the way the idx was working, i never felt the need to buy a commercial detector as they would of had a hard time being better.

[Tibuck19]

is your depth the same in pinpoint and all metal


whats the peak to peak on the TX neads to be measured on a scope.

I wanted to replace the MPSA but have not because Digikey had none in stock, i have desperately digging throw my pile of salvage compintents hoping i can find something to replace it with, i have already robbed the one out of the Original Cuda, As for pinpointing, it was always weaker on pinpoint ( AKA the threshold audio humming) then it was on beep mode, i would say, a little less than half the depth, if that is what you are asking? i am in the middle of putting all new wires harness together to for each part of the detector, as soon as its done i will fire up the idx and try to measure the TX with the scope and let you know what it is.

[tomec123]

:-))) yes, thats true ;-) . 35cm is very very good for this Project.

[Koala]

is your depth the same in pinpoint and all metal


what's the peak to peak on the TX needs to be measured on a scope.

[Koala]

its probably over 10 years since I last looked at the IDX


fairly confident all but two resistors measure okay in circuit and they on the PSU side


I vaguely remember testing them all while chasing poor depth in pinpoint mode


I had substituted MPSA13 for something else. Cant remember what should have been better but when I changed to MPSA14 i(I think) it was all good

[Tibuck19]

i have two years of using the 6b coil that says they work really well hahaha, I did have to remove 2k2 resistor and jumper it, which if i'm not mistaken, you were the one that had suggested it, which worked like a charm as i never had a problem ground balancing any of the coils including the 6b and the F coil, don's coil works really well however, it was always more noisy in parks where there was a lot of wifi around unlike the whites coils, that were always dead silent even at almost full sensitivity on the pot setting, like i said everything just worked and worked great till it didn't. i just finished taking all the connectors on the board of and re made all new connection hopping maybe some where there was a little fault. Silverdog was kind enough to send me a board, if it still doesn't work, i will simply repopulate a new board and give that a try. I don't know if it helps but, before nickels would not get detected about halfway on the 10K pot, now its more like 3/4 of of the way before they get discriminated out, I am thinking somewhere on the board there is probably a resistor or two that failed but pulling every single one out to test it out of circuit does not seem like a fun time.




i never ended up getting the vid finished and working lol

[Koala]

It is indeed the 8 inch is a 6b one of my 10inch is an F the other was made by dfbowers and the 15inch is another 6b however i have not hooked it up yet. The 8 inch and 10 inch coils are the coils i have been using with this IDX since day one, i never had problems with either one of them.

that's interesting

the 6b shouldn't ground balance.

they were for the lower classic range. The I,II,III,ID and IDX all used the same PCB however there were different jumpers for different models so you can adjust some resistors to make it work. I have forgotten which but if you look on the original schematics its easy to work out.


I have a couple of 6B coils. They never preformed as good as my homemade ones. Even with the circuit adjusted.


But were super stable.

[Tibuck19]

It is indeed the 8 inch is a 6b one of my 10inch is an F the other was made by dfbowers and the 15inch is another 6b however i have not hooked it up yet. The 8 inch and 10 inch coils are the coils i have been using with this IDX since day one, i never had problems with either one of them.